The Diagnosis: Meralgia paresthetica, caused by nerve compression: Stiff denim can squeeze a sensory nerve that runs across the front of the pelvis.

The Cure: If your pants are indeed at fault, "switching to looser ones should clear up the problem," says Christopher Luzzio, MD, a neurologist at the University of Wisconsin. If that doesn't help, you may need physical therapy, an injection, or even, in very rare cases, surgery.